BIO 123 Lecture Notes - Lecture 9: Bivalvia, Benthos, Mollusca
Document Summary
Body plan: organisms use to help organize all the animals on the planet. Presence or absence of a body cavity. Sea jelly, jelly fish - not fish because it doesn"t have a vertebrate. Hot water (as hot as you can stand) not peeing. Possess muscle and nerve tissue (allo movement) Early embryonic development gives rise to germ layers. Gives rise to skin and nervous system. Becomes muscles, connective tissue, skeleton, kidney, circulatory and reproductive organs. Cells will form the lining of the guy and major organs derived from it. No body cavity, no coelom, only digestive cavity. Sort of body cavity (btw mesoderm and endoderm), digestive cavity. True body cavity (fully surrounded by mesoderm), also digestive cavity, body cavity (coelom) Take food in same opening and release through same opening. Cushioning organs are metameric: body divided in segments. If you cut off end it will grow new tail but not new head.
